Drawing die assembly with integral cooling system in die housing

ABSTRACT

A pressure drawing die designed for drawing wires, rods and tubes made of materials having varied mechanical properties, whereby use is made of the effect of hydrodynamic friction. The drawing die incorporates a system of dies with a pressure sleeve with hydrodynamic action. A cooling system is built into the drawing-die body or housing. The inlet portion of the pressure sleeve extends outside the body through the orifice in a pressure nut. Between dies a seal in a form of labyrinths and metal powders is provided. The working dies are provided with metal jackets which separate the die core from the pressure mounting.

Prajsnar et al.

DRAWING DIE ASSEMBLY WITH INTEGRAL COOLING SYSTEM IN DIE HOUSINGInventors: Tadeusz Prajsnar; Jtizef Rulii'iski,

both of Gliwice; Edward Zglobicki, Zabrze; Ryszard Lyzwinski, Sosnowiec;Ireneusz Lacheta, Katowice; Aleksander Szczepanik, Katowice; StanislawPiaskowski, Katowice; Adam Godyli, Gliwice, all of Poland lnstytutMetalurgii Zelaza, Gliwice, Poland Filed: Feb. 16, 1971 Appl. No.:115,396

Assignee:

References Cited UNITED STATES PATENTS l/l940 Brandt 72/342 June 26,1973 2,753,261 7/1956 Goetzel 72/467 3,535,824 10/1970 Kessler ..49/4ss3,017,017 1/1962 Bruestle ..72/342 Primary Examiner-Charles W. LanhamAssistant Examiner-Robert M. Rogers Attorney-Karl F. Ross [57] ABSTRACTA pressure drawing die designed for drawing wires, rods and tubes madeof materials having varied mechanical properties, whereby use is made ofthe effect of hydrodynamic friction. The drawing die incorporates asystem of dies with a pressure sleeve with hydrodynamic action. Acooling system is built into the drawing-die body or housing. The inletportion of the pressure sleeve extends outside the body through theorifice in a pressure nut. Between dies a seal in a form of labyrinthsand metal powders is provided. The working dies are provided with metaljackets which separate the die core from the pressure mounting.

7 Claims, 7 Drawing Figures PAIENIEB M28 I913 3. 740,990

sum 1 I '3 Fig.2

INVENTOR ATTORNEY PAVIENIEDJIIKZB Ian armors Fig.4 I

INVENTOR ATTORNEY I DRAWING DIE ASSEMBLY WITH INTEGRAL COOLING SYSTEM INDIE HOUSING FIELD OF THE INVENTION The invention relates to the diedesigned for drawing wires, rods, and tubes made of material havingvaried mechanical properties, using the effect of hydrodynamic friction.

BACKGROUND OF THE INVENTION Two-part drawing assemblies which consist oftwo dies: the working die and the thrust die, made in a form of sintercores, divided by a gasket, built into a collet and enclosed in thecommon casing consisting of a body (housing) and a nut, are known.

With this drawing die, it is possible to build in, instead of the thrustdie, a pressure sleeve, with a view to obtaining a higher lubricantpressure, whereby, for each sleeve length another body is employed. Thissleeve is located entirely inside the body or housing.

Another known design is represented by a die provided with a mountinginside which a die made of sintered carbides, a gasket, and a sleevewith flange are placed. This die is designed for drawing wires with theuse of liquid lubricants.

Still another system uses a pressure die in which pressure is obtainedby means of pumps.

In some other designs a working die made of sintered carbides with ametal mounting is used; however, the outer diameter of the mountingamounts to more than 1.4 times the outer diameter of the die core,whereby, in these cases a clamping device is not employed.

All these designs do not provide satisfactory results. They do notguarantee constant pressures and with the progressing use of the systemor changing dimensions of the blank being drawn are not able to ensurefluid friction. Besides, the designs described above make it necessaryeach time the dimension or production program is changed, to change alsothe casing of the pressure drawing die.

OBJECT OF THE INVENTION The object of the invention is the developmentof such a pressure die, which with unchanged overall dimensions of theclamping sleeve, casing, and pressure seat of the die, will ensure ahydrodynamic lubrication in drawing a material of any kind. This objectis achieved with a pressure die assembly incorporating a tandem systemof dies with pressure sleeves with hydrodynamic action, whose body orhousing includes a permanently built-in cooling system, and a pressuresleeve, whose outlet part partly extends outside the body through theorifice in the clamp nut.

Between the dies and the die and pressure sleeve a seal in the form ofmetal rings or metal powder is providedflhe working dies have a metaljacket which separates the core of the working die from the clampingmounting.

The working dies and the pressure sleeve are provided with cooperatinglabyrinths forming seals. A version of the die, according to theinvention, has working dies whose core has only the die reduction angleand the calibrating part.

The pressure die also may have a plurality of working dies, whereby, thefirst die downstream of the pressure sleeve is the thrust-working die,i.e., depending on needs, this die deforms the metal being drawn, or itreduces the diameter of the sleeve orifice.

DESCRIPTION OF THE DRAWING The invention is illustrated in theaccompanying drawing, in which:

FIG. 1 is a longitudinal section of the universal pressure die;

FIG. 2 is a cross-section through the pressure sleeve of the universaldie;

FIG. 3 is a cross-section through the cooling system of the universaldie;

FIG. 4 is a section through a die;

FIG. 5 is a section through the seal; and

FIG. 6 and FIG. 7 are sections of other versions of the seal.

SPECIFIC DESCRIPTION FIG. 1 shows the die according to invention, whichhas the body 1 with a permanently built-in cooling system. In the body 1the centering clamp sleeve 8 tapered complementary to the wall of body 1in contact therewith, away from the threaded end of the body is located,inside which are provided working dies 4 and 5, and the pressure sleeve3, whose outlet part extends outside the die through the orifice in theclamp nut 7 which bears on a shoulder of the pressure sleeve. Betweenthe dies 4 and 5 and the pressure sleeve 3 a seal 6 is included. Thecooling channel 2 (FIG. 1) axially spans both dies for the collectivecooling thereof.

In FIG. 2 the pressure sleeve 3 is shown; the sleeve 3 has the inletpart 9, orifice 10 through which the metal being drawn passes, theoutlet part 11, the labyrinth undercut 13, whereby the orifice 10 in theoutlet part 11 has a widening or enlargement 12.

In FIG. 3 the cooling system of the universal die is shown, whichconsists of the chamber of the cooling cycle 14 built in the body 1 ofthe die, whereby, for the proper circulation of the cooling agent, thechamber is divided by the rib 15.

The structural details of the working die 4 and 5 are shown in FIG. 4which comprises the metal jacket 16, inside which the core 17 made ofsintered carbides is provided, whereby, the die has the die reductionangle 18, and the calbrating part 19, as well as the labyrinth undercuts20 that cooperate with labyrinth undercuts 13 of the pressure sleeve 3.

FIG. 5 shows the seal 6 which consists of inner gasket 23, outer gasket22 of the thrust ring 21, and the sealed elements 24 and 25, which maybe working dies, or working die and pressure sleeve. The version of theseal 6, according to invention, as shown in FIG. 6 has the labyrinthundercut 27 in the form of a flange.

The other version of the seal 6 shown in FIG. 7 has an outer gasket 26made of metal powders.

The material being drawn passes through the pressure sleeve 3 and theworking dies 4 and 5, and produces in the slot between the pressuresleeve 3 and working die 5 and the material being drawn a high pressureof the lubricant, which at the inlet of the die reduction angle reachesthe value of plasticity limit of material being drawn, and at the sametime provides hydrodynamic lubrication.

Among the advantages of the universal die, according to invention, isthe fact that it can be operated as the singleor multi-stage die,whereby, no change of the casing for working dies with different coresizes and at different sleeve lengths are required.

The die makes it possible to obtain pressures up to 15,000 atmospheresand provides fluid lubrication for each material to be drawn. One of themost important advantages is the fact that the die enables the obtainingof considerable deformations at a raised drawing speed, as compared withspeeds achieved up to now.

We claim:

1. A drawing die comprising a housing formed with a unitary tubularhousing body provided integrally with an axially extending annularcoolant channel, and means for passing a fluid through said channel tocool the interior wall of said housing body; a pair of dies axiallyaligned along said housing body and collectively cooled thereby, saidchannel axially spanning both said dies and at least partly surroundingsame; a pressure sleeve ahead of said dies and axially alignedtherewith, said pressure sleeve having an annular shoulder; a centeringsleeve in contact with said wall and said dies and coaxially nestedtherewith for conducting heat between said body and said dies, saidclamping sleeve and said wall having complementary tapers away from saidshoulder; and a clamping nut threaded onto an end of said housingleading in the direction of drawing, said clamping nut having an axialorifice and bearing upon said shoulder in the direction of taper of saidwall, said pressure sleeve having an axially extending portion tra- 4versing said orifice, said dies being in axially abutting engagement.

2. The assembly defined in claim 1, further comprising a metal annularseal between said dies and said pressure sleeve.

3. The assembly defined in claim 2 wherein said seal is composed ofmetal powder.

4. The assembly defined in claim 1 wherein said housing includes ajacket surrounding said housing body and defining an annular compartmenttherein, respective ducts connected with said jacket for leading acooling fluid to and removing the cooling fluid from said compartment,and a rib in said compartment partitioning the same.

5. The assembly defined in claim 4 wherein at least one of said dies hasa sintered carbide body, a metal jacket surrounding and receiving saidsintered carbide body, and a clamping sleeve receiving said metal jacketand said sintered carbide body within said housing body, the height ofsaid metal jacket being between 1.0 and 1.4 times the height of saidsintered carbide body.

6. The assembly defined in claim 5 wherein said dies and said pressuresleeve are formed with co-operating labyrinths.

7. The assembly defined in claim 6 wherein said sintered carbide bodyonly has the die reduction angles and calibrating bore.

1. A drawing die comprising a housing formed with a unitary tubularhousing body provided integrally with an axially extending annularcoolant channel, and means for passing a fluid through said channel tocool the interior wall of said housing body; a pair of dies axiallyaligned along said housing body and collectively cooled thereby, saidchannel axially spanning both said dies and at least partly surroundingsame; a pressure sleeve ahead of said dies and axially alignedtherewith, said pressure sleeve having an annular shoulder; a centeringsleeve in contact with said wall and said dies and coaxially nestedtherewith for conducting heat between said body and said dies, saidclamping sleeve and said wall having complementary tapers away from saidshoulder; and a clamping nut threaded onto an end of said housingleading in the direction of drawing, said clamping nut having an axialorifice and bearing upon said shoulder in the direction of taper of saidwall, said pressure sleeve having an axially extending portiontraversing said orifice, said dies being in axially abutting engagement.2. The assembly defined in claim 1, further comprising a metal annularseal between said dies and said pressure sleeve.
 3. The assembly definedin claim 2 wherein said seal is composed of metal powder.
 4. Theassembly defined in claim 1 wherein said housing includes a jacketsurrounding said housing body and defining an annular compartmenttherein, respective ducts connected with said jacket for leading acooling fluid to and removing the cooling fluid from said compartment,and a rib in said compartment partitioning the same.
 5. The assemblydefined in claim 4 wherein at least one of said dies has a sinteredcarbide body, a metal jacket surrounding and receiving said sinteredcarbide body, and a clamping sleeve receiving said metal jacket and saidsintered carbide body within said housing body, the height of said metaljacket being between 1.0 and 1.4 times the height of said sinteredcarbide body.
 6. The assembly defined in claim 5 wherein said dies andsaid pressure sleeve are formed with co-operating labyrinths.
 7. Theassembly defined in claim 6 wherein said sintered carbide body only hasthe die reduction angles and calibrating bore.